ENGLISH ABSTRACT: Ultrafast Electron Diffraction (UED) is a rapidly maturing field which allows investigation of the
evolution of atomic arrangement in solids on timescales comparable to the vibrational period of
their constituent atoms (~10-13 s). The technique is an amalgamation of conventional high energy
electron diffraction methods and pump-probe spectroscopy with femtosecond (1 fs = 10-15 s) laser
pulses. Ultrafast pulsed electron sources generally suffer from limitations on the attainable electron
number per pulse (brightness) due to Coulomb repulsion among the electrons. In this dissertation,
the design and construction of a compact UED source capable of delivering sub-300 fs electron
pulses suitable for diffraction experiments and containing about 5000 electrons per shot is
described. The setup has been characterised by measurement of the transverse beam size and
angular spread, and through recording and analyzing an electron diffraction pattern from a titanium
foil. Measurement of the temporal duration of fs electron pulses is not trivial, and a specialised
compact streak camera operating in accumulation mode has been developed as part of this study. A
sub-200 fs temporal resolution has been achieved, and the dependence of temporal duration on
electron number per pulse was investigated for the current UED source. The observed trends
correlate well with detailed electron bunch simulations. In order to investigate ultrafast processes on
samples that cannot be probed repeatedly, it becomes necessary to significantly increase the
brightness of current state of the art compact sources such as the one constructed in the present
study. UED sources employing electron pulse compression techniques offer this possibility.
Traditional pulse compression schemes based on RF cavities, while simple in principle, pose
significant technical challenges in their realisation. The current thesis describes two novel UED
pulse compression methods developed by the author: achromatic reflectron compression and pulsed
cavity compression. Both concepts are expected to be easier to realise than conventional RF
compression. Detailed simulations predict that such sources can attain a brightness improvement of
more than one order of magnitude over compact sources that do not employ compression
techniques. In addition, such sources show much promise for the attainment of pulse durations in
the sub-100 fs range.